The shipbuilder said it would also design the 17,000-cbm trailing hopper units.
The 158-metre ships will be delivered in 2017. No contract price was revealed.
They will be equipped with two suction pipes with submerged electric pumps and be able to accommodate 38 people.
La Naval said it beat other European yards to the deal.
It is Van Oord’s first order at the Spanish shipbuilder.